1. Field of the Invention
The present invention relates to a lateral guidance apparatus for a cross-country ski boot, including a longitudinal rib which projects from the upper surface of a ski, as well as a cross-country ski and boot adapted for this purpose.
2. Description of Background and Relevant Information
Cross-country skis which include a longitudinal rib on their upper surfaces are known. This rib can form an integral portion of the ski or it can be formed on a plate which is itself affixed to the upper surface of the ski. Such a rib generally has a generally trapezoidal cross-section. Otherwise stated, it is defined by an upper horizontal surface and two lateral inclined surfaces. The upper longitudinal rib contributes to the lateral guidance of the boot mounted on the cross-country ski, which is adapted for this purpose by virtue of the provision of a groove in its sole having a complementary shape in cross-section to that of the rib of the ski. During the flattening of the foot on the ski during the practice of cross-country skiing, the groove of the sole, in effect, progressively caps the lateral guidance rib which intervenes to laterally maintain the boot, and preferably well-centered, on the ski.
Cross-country skiers more and more often use a "skating" or "half-step skating" technique in which the skier, to ensure his or her propulsion on at least one of the skis, inclines the ski with respect to its direction of movement. Yet, with such a technique the skier often has a tendency to take "too much edge," i.e., there is an increased tendency for the skier to twist his or her ankle.